Unfortunately I don’t think its quite that straight forward. Not all SMPS are crap.
One of the reasons I try to avoid them is that they feed noise back into the mains. This may be important if for example you have a dedicated mains supply.
Some equipment can cope very well with any noise they deliver.
I’m not SB user, but people here who use them seem to recommend a linear supply writing it makes an audible difference. There is quite a bit on this site regarding linear supplies for the SB so a bit of a search may prove fruitful.
Single spur balanced Mains. Self built music server with 3 seperate linear PSU, Intel i5, 16 GB RAM no hard drive (various Linux OS). Benchmark Dac2 HGC, single ended XLR interconnects/Belkin cable. Exposure 21RC Pre, Super 18 Power (recap & modified). Modded World Audio HD83 HP amp. Hand built Monitors with external crossovers , Volt 250 bass & ABR, Scanspeak 13M8621 Mid & Scanspeak D2905/9300 Hi. HD595 & Beyer 880 (600 ohm) cans.
The whole problem with the world is that fools and fanatics are always so certain of themselves, and wiser people so full of doubts.
-Bertrand Russel
John.